الفهرس | Only 14 pages are availabe for public view |
Abstract ”Hydrometallurgical Processing of Egyptian Zinc Concentrate for Preparation of Nano Crystalline Zinc Oxide Materials for Advanced Applications” ABSTRACT ZnO with different morphologies have been synthesized from Egyptian zinc concentrate as well as pure chemicals using co-precipitation and hydrothermal strategies. Zinc concentrate was first leached with H2SO4 to form water soluble zinc sulfate which chemically precipitated with NH4HCO3 and thermally treated at 500 ⁰C for 1h. Furthermore, the effect of surfactants (CTAB, AOT and PEG) on the crystal structure, microstructure, optical properties and photocatalytic degradation towards methylene blue dye was investigated. In this context, good high photocatalytic efficiency 90.8 % was accomplished with CTAB as a surfactant. Nevertheless, the impact of Sn2+ and Cu2+ ions on the crystal structure, microstructure, and optical properties of ZnO powders synthesized via co- precipitation route was also considered. Meanwhile, the photocatalytic degradation of MB using 5% Sn2+ substituted ZnO was 96 %. Otherwise, the obtained powders were tested of solid state dye sensitized solar cell. For instance, the power conversion was arrived to 4.3 % for the 5% Sn2+ ion substituted ZnO compared with the pure ZnO. Alternately, ZnO micro/nanorods have been successfully synthesized via hydrothermal technique as well as ZnO micro/nanorods deposited by TiO2 layers was synthesized by atomic layer deposition method. Indeed, these materials were tested for photoelectrochemical water splitting. The results revealed that the deposition of TiO2 with 50 cycles exhibited 45 % decrease in the dark current compared with the pure ZnO micro/nanorods. |